This application is based upon and claims the benefit of priority from the prior Japanese Patent Application No. 2001-223480, filed Jul. 24, 2001, the entire contents of which are incorporated herein by reference.
1. Field of the Invention
The present invention relates to a microscope, and more particularly, to a microscope for converting an observed image of a specimen, such as cellular tissue or a microorganism, into a picture signal to be observed.
2. Description of the Related Art
Computers are utilized in the field of education nowadays. Computerized education is expected to cover various courses of study that utilize actual computers, as well as simple computer training.
In science education, for example, cellular tissue, microorganisms, etc. are directly observed with use of microscopes, and besides, their observed images are supposed to be converted into picture signals, which are to be observed on computers.
A conventional microscope that can generate those picture signals is described in Jpn. Pat. Appln. KOKAI Publication No. 10-333055. In this microscope, a lens unit is located next to a specimen stage portion, and a CCD unit is situated on a bent optical path that extends from the lens unit. In acquiring a picture signal, a specimen or sample is placed on the specimen stage portion, and the stage portion is rotated to adjust the focus. Thereafter, an optical image of the specimen is formed by means of the lens unit. The optical image formed in this manner is guided through the bent optical path to a CCD image-pickup element of the CCD unit and converted into electric information, whereupon a picture signal is generated.
In the microscope described above, however, the optical image that is fetched by means of the lens unit is guided to the CCD image-pickup element through the bent optical path. Therefore, the microscope requires use of a lot of essential optical parts, so that its construction is complicated and its optical performance is not very high.
According to this conventional microscope, moreover, the focus is adjusted by rotating the specimen stage portion, so that the direction and position of the specimen on the stage portion inevitably shifts during the focus adjustment. Accordingly, its imaging range or picture frame is unstable, so that the microscope is not easy to handle. It is very hard for this microscope, in particular, to acquire picture data of specimens or sample that have directional shapes, among other specimens or sample including cellular tissue and microorganisms that are observed in educational scenes.
As described above, the conventional microscope has a slim optical structure such that the optical image is guided to the CCD image-pickup element through the bent optical path. Thus, the optical path is so complicated that the optical performance of the microscope is poor.
According to an aspect of the invention, there is provided a microscope for observing a sample to output an electrical image information relating to an image of the sample, comprising:
a stage portion configured to permit the sample to be mounted;
an image-pickup element, on which an optical image of the sample is formed, configure to convert the optical image into the electric image information,
an optical system, having the optical axis extending in a straight line between the stage portion and the image-pickup element, configured to guide the optical image of the sample to the image-pickup element;
a light source unit including one light source configured to emit an illumination light beam for illuminating the sample and a mechanism configured to alternatively locate the light source in any of first, second, and third irradiative positions for transmissive illumination, incident illumination, and oblique illumination, thereby selecting one of the transmissive illumination, incident illumination, and oblique illumination.
According to an another aspect of the invention, there is provided a microscope for observing a sample to output an electrical image information relating to an image of the sample, comprising:
a stage portion configured to permit the sample to be mounted;
an image-pickup element, on which an optical image of the sample is formed, configured to convert the optical image into the electric image information,
an optical system, having the optical axis extending in a straight line between the stage portion and the image-pickup element, configured to guide the optical image of the sample to the image-pickup element;
an optical lens barrel portion, the image-pickup element and the optical system being arranged the optical lens barrel portion; and
a stage moving mechanism configured to support the stage portion on the optical lens barrel portion and move the stage within a plane substantially perpendicular to the optical axis.
According to an another aspect of the invention, there is provided a microscope for observing a sample to output an electrical image information relating to an image of the sample, comprising:
a stage portion configured to permit the sample to be mounted;
an optical system, located under the stage portion and including a zoom lens unit, configured to form the optical image of the sample;
an image-pickup element, which is arranged in the image forming position of the optical system for the sample and on which the optical image is formed, configured to convert the optical image into the electric image information,
an external output portion configured to convert the electric image information generated from the image-pickup element into a picture signal and delivering the signal to the outside of the microscope;
a base portion configured to hold the image-pickup element and the external output portion;
a support structure configured to support the stage portion on the base portion and also support the optical system;
a zoom control portion, located between the base portion and the stage portion, configured to move the zoom lens unit along the optical axis; and
a focus adjusting mechanism, supported under the stage portion by means of the support structure, configured to focus the optical system on the sample.